Women are waiting longer to have babies, according to a report that shows almost one-third of first-time mothers in 1997 were aged 30 or older.

Compared to 19% a decade earlier, 31% of first-time births in 1997 were to women older than 30.

In Ontario, half of all births in 1997 were to mothers older than 30, up from one-third in 1987. However, the numbers were lower in Saskatchewan and the Northwest Territories where first-time mothers aged 30 made up for less than 20%.

The 1997 statistics indicate that the fertility rate -- the average number of babies a woman will have during her life -- was 1.5. That rate, significantly lower than in 1950 when women gave birth to an average 3.9 babies, is lower than the necessary replacement rate of two that sustains the population.

Nationally, the proportion of births to teenage girls remained at 6% over the decade spanning 1987-1997.

Janet Salaff, a sociology professor at the University of Toronto, says the class demographic of a woman is an important factor when considering the results. Whether the woman comes from a working, middle or upper-class background will likely affect her decision to have children at a younger age based on her financial situation and value system.

As well, the professor points to the different interests young adults have to explain the trend to postpone pregnancy. "Before, people used to generally do the same things, but now there are so many people with diverse lifestyles."

She says in addition to having different priorities such as education, travel or career, they are less likely to make early commitments, like having children, for fear of missing other opportunities.

There has been a decline in twentysomething women giving birth throughout the decade spanning 1987-1997. In 1987, 31% of women older than 30 were having children; 44% of all live births were to women of this age group in 1997.